The sighting of mammals underwater in the
central and southern Aegean and Mediterranean coasts of Turkey is very rare. Less rare are
sightings of Dolphins and Turtles on the surface which are often seen from diveboats'
travelling between dive sites.

The distribution of Dolphins in the
Mediterranean and Aegean Seas is governed largely, if not exclusively, by the availability
of food. In global terms the waters of the Mediterranean are relatively unfertile and do
not produce the food quantities required to sustain large groups of dolphins. This makes
their appearance around the Turkish diving areas rare and then often only small social
groups of between five and ten animals are seen. There are marginally more sightings along
the southern, Mediterranean Coast of Turkey.

The south western region of Turkey is an
important area for the loggerhead turtle which returns each year to breed in the area
around Dalyan. Dalyan is at the southernmost point of the Aegean coastline of Turkey and
the beaches provide the perfect place for the turtles to lay their eggs.

Mollusca have chalky shells, except
octopus and sea slugs, a wide range of color and shell pattern, often a yellow fleshy
body and no obvious body segments. Species include Octopus, Snails, Sea Slugs,
(Nudibranchs) and Bivalves.

The sea hare is a gastropod and normally
lives among weeds in shallow water. They can often be seen swimming with what appear to be
wings. They have four head tentacles, the rear pair are large and resemble the ears of a
hare. When mature they reach 25cm long and brown green in color, sometimes with white
spots, younger specimens are a reddish brown color. If threatened they sometimes eject a
harmless purple dye.

This mollusc is a carnivorous predator
preying on starfish and other slow moving animals. They have a large cone shaped spiral
shell up to 20cms in length colored brown yellow orange, matching to some extent their
habitat among rocks and weed over which they are fairly mobile. They have two very
distinctive retractable pointed black and yellow banded head antennae branching out in
front of their eyes

This species of a familiar mollusc can
be found in shallow sandy bays in great numbers during July and August. It has a short
siphonal canal and a long slit like opening with a straight, sharp outer edge. They have a
single sharp, venomous hollow tooth which they flick out to inject their prey or in
defense if they are threatened. If mishandled by divers the venom can cause varying levels
of pain. Fortunately the Mediterranean species are not as poisonous as their tropical
relatives.

There are many species of cowries of
varying sizes and colors. Their most distinctive feature is the long slit like opening
running from end to end and a very smooth outer surface. In life the animal extends a thin
mantle over the exterior of their shell and this is the reason why these shells are so
smooth and have such a slippery feel. If they are disturbed the cowrie quickly withdraw
their mantle into their shell, emerging very slowly when no longer threatened.

Normally found in deeper water this
mollusc often burrows beneath the surface of the sand with only a small part of its round
shell visible. They feed on relatively large slow moving organisms like sea cucumbers,
which they ingest whole. The disproportionate volume of their prey often makes it
impossible for them to retreat into their shell, and is the reason why they seek
protection by burrow themselves into the sand. Empty shells, sometimes up to 150cms in
diameter, can often be found in less dived areas.

These often highly colored
Opisthobranchs lack a shell, have obvious naked gills and a pair of head tentacles. The
gills and tentacles are retracted quickly into the body if they are disturbed or
threatened.

Many small species of nudibranch exist
in Turkish waters. Particularly common is a bright violet colored species which can often
be seen clinging to seaweed or marine plants with its fragile appendages waving even in
the slightest of currents. Another common variety to be found clinging to rocks or to the
surface algae is (Peltodoris atromaculata), which has a flat oval light cream colored
body with dark brown patches. Generally between 1cm to 4cm in length they can occasionally
reach up to 6cms long, there are two unbranched head tentacles and 9 branching gills in a
ring on the back.

Sponges are sessile animals whose bodies consist
of a single cavity with a major exhalent opening and many smaller inhalant openings. The
bodies also contain calcareous or siliceous spicules, or horny fibers, which provide
support and exist in almost every color imaginable. There are three classes of sponge,
Calcarea, Hexactinellida and Demospongiae, and over 1000 species. Sponges often resemble,
and are mistaken for plants. Unlike plants, which rely rely on sunlight for
photosynthesis, sponges inhabit both the shallow and deep water regions of the worlds seas
and oceans.

The seas around the coast of
Turkey were once important sponge producing areas, but the collectible bath sponge,
(Spongia officinalis) no longer exists in commercially viable quantities. Many other
species of sponge do flourish here and are too numerous to list in this guide. Anyone with
a particular interest in finding, identifying and cataloguing the sponges which inhabit
Turkish waters will find a wealth of study here.

Surface encrusting sponges are numerous
and can be seen at all depths. They are distinctive, being smooth, often with a slimy feel
and many exhalent holes over the surface. There are a wide range of species in Turkish
waters in a variety of colors from bright red, green, brown and black.

These thrive on the predominantly rocky
terrain around these shores and many examples can be seen on every dive and they are often
mistaken for Nudibranchs. Sometimes quite mobile, look out for the small brown species
with white irregular spots and two tentacles at the head which they quickly retract if
they feel threatened.

Bristle worms are a very successful
species which has been scavenging the bottom of the shallowest seas and deepest oceans of
the world for millions of years. Usually to be found hiding under rocks and in crevices
during the day they venture out at night in search of carrion. During the mating season,
which is during mid summer in Turkey, certain species can be seen during the day standing
vertically on rocks either singly or in large writhing groups. They can grow to 15cm in
length and they resemble furry caterpillars, the fine poisonous hairs along the body
flaring white if disturbed. While they are not dangerous to divers, contact with the skin
can result in irritation which can be quite painful and last for several hours.

This species of worm belongs to the
family Sabellidae, which are tube dwelling polychaetes. This species common in Turkish
waters, has flower like gills consisting of between 8 to 45 filaments which fan out at the
top of the membranous tube. If disturbed the gills retract quickly into the tube.

These solitary or colonial organisms
grow attached to rocks and consist of a tube shaped body made a material resembling
cellulose. At the top of the body is an inhalant siphon and on the side of the body is an
exhalent siphon. Water is pumped through the body where food and oxygen are extracted.
There are several species in Turkish waters.

The red sea squirt is the most common
species of sea squirt in Turkish waters, it is soft and smooth and appears to be red brown
in color, though on night dives they are bright red by torch light. If disturbed they
close their distinctive, four leafed inhalant siphon and contract their body becoming
hard. More difficult to find but nonetheless numerous, is a dark brown species resembling
encrusted rock, which can be up to 20cms long and usually found hanging under overhanging
rocks. If disturbed, the whole organism contracts strongly closing both inhalant and
exhalent openings.